1. Field of the Invention
The present invention relates to a control system for a motor including a motor and controlling means for controlling the rotation of the motor.
2. Description of the Related Art
A manufacturing device such as an arm or the like used in a process of manufacturing a semiconductor or the like uses a control system for a motor that detects the rotation angle of a motor as a source of power to the manufacturing device and which controls the rotation of the motor on the basis of the detected rotation angle. An ordinary configuration of such a control system for a motor is composed mainly of a motor unit including a motor and detecting means for detecting the rotation angle of the motor and controlling means (driver) for controlling the rotation of the motor, the controlling means being electrically connected in a replaceable state to the motor unit. In order to be used in a manufacturing device such as an arm or the like, the detecting means uses a resolver capable of detecting a rotation angle even in a state of the rotation of the motor being stopped. However, as shown in FIG. 3, there is an error between the rotation angle detected by the resolver (which rotation angle will hereinafter be referred to also as a detected angle) and an actual rotation angle (which will hereinafter be referred to also as an actual angle). This error is a factor in hindering fine rotation control, and is different for each motor unit (the motor and the resolver).
A conventional control system for a motor described in Japanese Patent Laid-Open No. 2005-329478, for example, stores error data between a rotation angle detected by a resolver and an actual angle in a storing section of controlling means in order to determine the actual angle from the rotation angle detected including the error, and determines the actual angle by making a correction that subtracts an error value from the detected rotation angle using the error data.